feat: add PyFaceBlur TUI app with welcome screen and path autocomplete

src/faceblur/app.py

@@ -0,0 +1,167 @@
+"""PyFaceBlur TUI application."""
+
+import os
+from pathlib import Path
+
+# Set model cache before any uniface imports
+os.environ.setdefault(
+    "UNIFACE_CACHE_DIR",
+    str(Path(__file__).resolve().parent.parent.parent / "models"),
+)
+
+from textual.app import App, ComposeResult
+from textual.binding import Binding
+from textual.containers import Center, Middle, Vertical
+from textual.screen import Screen
+from textual.widgets import Button, Footer, Input, Label, Static
+from textual_autocomplete import PathAutoComplete
+
+
+LOGO = r"""
+ ____        _____              ____  _
+|  _ \ _   _|  ___|_ _  ___ __|  _ \| |_   _ _ __
+| |_) | | | | |_ / _` |/ __/ _ \ |_) | | | | | '__|
+|  __/| |_| |  _| (_| | (_|  __/  _ <| | |_| | |
+|_|    \__, |_|  \__,_|\___\___|_| \_\_|\__,_|_|
+       |___/
+"""
+
+
+class WelcomeScreen(Screen):
+    """Welcome screen with video path input and settings."""
+
+    DEFAULT_CSS = """
+    WelcomeScreen {
+        align: center middle;
+    }
+
+    #app-container {
+        width: 60;
+        height: auto;
+        max-height: 24;
+        border: round $accent;
+        padding: 1 2;
+    }
+
+    #logo {
+        text-align: center;
+        color: $text;
+        text-style: bold;
+        margin-bottom: 1;
+    }
+
+    #video-input {
+        margin-bottom: 1;
+    }
+
+    #interval-input {
+        width: 20;
+        margin-bottom: 1;
+    }
+
+    #start-btn {
+        margin-top: 1;
+        width: 100%;
+    }
+
+    #error-label {
+        color: $error;
+        text-align: center;
+        display: none;
+    }
+
+    .field-label {
+        margin-bottom: 0;
+        color: $text-muted;
+    }
+    """
+
+    def compose(self) -> ComposeResult:
+        with Center():
+            with Middle():
+                with Vertical(id="app-container"):
+                    yield Static(LOGO, id="logo")
+                    yield Label("Video file:", classes="field-label")
+                    video_input = Input(
+                        placeholder="Enter path to video file...",
+                        id="video-input",
+                    )
+                    yield video_input
+                    yield PathAutoComplete(target=video_input, path=".")
+                    yield Label("Frame interval:", classes="field-label")
+                    yield Input(
+                        value="30",
+                        placeholder="Frame interval",
+                        id="interval-input",
+                        type="integer",
+                    )
+                    yield Label("", id="error-label")
+                    yield Button("Start", id="start-btn", variant="primary")
+
+    def on_button_pressed(self, event: Button.Pressed) -> None:
+        if event.button.id == "start-btn":
+            self._validate_and_start()
+
+    def _validate_and_start(self) -> None:
+        video_path = self.query_one("#video-input", Input).value.strip()
+        interval_str = self.query_one("#interval-input", Input).value.strip()
+        error_label = self.query_one("#error-label", Label)
+
+        if not video_path:
+            error_label.update("Please enter a video file path.")
+            error_label.styles.display = "block"
+            return
+
+        path = Path(video_path)
+        if not path.exists():
+            error_label.update(f"File not found: {video_path}")
+            error_label.styles.display = "block"
+            return
+
+        try:
+            interval = int(interval_str)
+            if interval < 1:
+                raise ValueError
+        except ValueError:
+            error_label.update("Frame interval must be a positive integer.")
+            error_label.styles.display = "block"
+            return
+
+        error_label.styles.display = "none"
+        self.app.push_screen(ProcessingScreen(video_path=path, interval=interval))
+
+
+# Forward declaration — ProcessingScreen will be added in Task 5
+class ProcessingScreen(Screen):
+    """Placeholder — replaced in Task 5."""
+
+    def __init__(self, video_path: Path, interval: int) -> None:
+        super().__init__()
+        self.video_path = video_path
+        self.interval = interval
+
+    def compose(self) -> ComposeResult:
+        yield Label(f"Processing {self.video_path}...")
+
+
+class PyFaceBlurApp(App):
+    """PyFaceBlur TUI application."""
+
+    TITLE = "PyFaceBlur"
+    CSS = """
+    Screen {
+        background: $surface;
+    }
+    """
+    BINDINGS = [
+        Binding("q", "quit", "Quit", show=True),
+    ]
+
+    def on_mount(self) -> None:
+        self.push_screen(WelcomeScreen())
+
+
+def run() -> None:
+    """Entry point for the TUI app."""
+    app = PyFaceBlurApp()
+    app.run()